1. Field of the Invention
The present invention relates to a heat exchanger for a hybrid electric vehicle, and more particularly, to a heat exchanger for a vehicle, in which a second radiator as a heat exchanger for cooling electronic components, such as an inverter and a motor, and a first radiator as a heat exchanger for cooling an engine are manufactured into an integral-type heat exchanger, and a reservoir tank is integrally coupled to the integral-type heat exchanger.
2. Background Art
In general, there are well-known vehicles which use an engine as a driving power source as well as hybrid vehicles which use an electric power source including a motor.
Such a hybrid vehicle is configured of a type in which an electric motor is coupled to a combustion engine, such as a gasoline engine or a diesel engine, and has been commercialized and put on the market abroad. The hybrid vehicle has a merit in that it can provide a high fuel consumption ratio and minimize the discharge of exhaust gas during the traveling in the downtown where the vehicle travels at a relatively low speed while repeating the stop and start operations, and hence it has been developed in various types also in Korea.
As described above, most of the hybrid vehicles, which are now being put on the market or developed, are mainly configured in a type in which the combustion engine and the motor are coupled with each other. Similarly to general vehicles, the hybrid vehicle must be equipped with an engine cooling system for keeping a proper temperature of the gasoline engine or the diesel engine as well as a separate cooling system for cooling a large amount of heat generated from the electronic components, such as an inverter for converting a DC current of a battery into an AC current for driving the motor.
Japanese Patent Laid-Open Publication No. 2001-59420 discloses a heat exchanger having an engine cooling system and an electronic component cooling system. The heat exchanger will be described hereinafter with reference to FIG. 1.
As shown in FIG. 1, the heat exchanger includes: an engine 1; a first water pump 6 receiving driving power from the engine 1 for circulating cooling water between the engine 1 and a first radiator 2; a second water pump 5 for circulating cooling water between an electronic component 11, such as an inverter, and a second radiator 3; a first reservoir tank 7 for storing cooling water when cooling water contained in the first radiator 2 overflows; a second reservoir tank 8 for storing cooling water when cooling water contained in the second radiator 2 overflows; a first injection port 9 for injecting or replenishing cooling water to the first radiator 2; and a second injection port 10 for injecting or replenishing cooling water to the second radiator 3.
The first radiator 2 and the second radiator 3 are formed integrally with each other in such a manner as to be stacked on top of each other.
However, the heat exchanger according to the prior art has the following problems.
First, since the first and second reservoir tanks 7 and 8 and the first and second radiators 2 and 3 are configured of separate components, an assembly process is complicated in which hoses or tubes is connected thereto for fluidically communicating the first and second reservoir tanks 7 and 8 with the first and second radiators 2 and 3, respectively, to allow cooling water to flow therebetween through the hose or tubes. In addition, since the first and second reservoir tanks 7 and 8 are mounted separately, there is a restriction in space in installing them at a small area inside the vehicle.
Second, since the first and second reservoir tanks 7 and 8 and the first and second radiators 2 and 3 are configured of separate components, manufacturing facilities for manufacturing them must be made independently due to their different manufacturing methods.